87 civic sputters? HELP!

Hi. I've got a problem. Do you have a solution? I was driving home yesterday and my 87 honda civic started to sputter. The engine won't go above 2000 rpm's without the car shaking. If I keep driving, staying under 2000 rpm's the car shifts gears just fine(it's an auto), but if i push the gas in too far, it starts it sputter. I also hear a noise, sort of a clicking sound when it sputters. And on top of that, when the car is in park, I can rev the engine above 2000 rpm's with no problem. Any ideas?

When was your last tune up?